HelenOS is a microkernel-based OS aiming to be a research vehicle for operating system design. Aesthetically, HelenOS resembles Windows 3.1 and 95 with nostalgic appeal. HelenOS is in early stages ...

Despite being an open-source operating system, Fuchsia OS isn't built on the Linux kernel. Instead, it's built based on Zircon, which is a microkernel developed from scratch by Google.

Despite this framing, Huawei’s microkernel appears to have Linux binary compatibility and reuses Linux drivers using driver containers — meaning it’s likely largely based on Linux.

HarmonyOS Next differs from Android with a microkernel, native app ecosystem, closed nature, better performance, and cross-device IoT integration for enhanced security.